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Date: Wed, 25 Sep 2024 10:44:42 -0700
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Subject: Re: Repeatable Read Isolation Level "transaction start time"
To: Greg Sabino Mullane <htamfids@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>
Cc: Wizard Brony <wizardbrony@gmail.com>, pgsql-general@lists.postgresql.org
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From: Adrian Klaver <adrian.klaver@aklaver.com>
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On 9/25/24 10:22 AM, Greg Sabino Mullane wrote:
> On Tue, Sep 24, 2024 at 10:28 AM Tom Lane <tgl@sss.pgh.pa.us 
> <mailto:tgl@sss.pgh.pa.us>> wrote:
> 
>     It's even looser than that, really: it's the first statement that
>     requires an MVCC snapshot.
> 
> 
> Hm....so why does "SELECT 1;" work as a transaction start marker then, 
> as opposed to "SHOW work_mem;", which does not? Do we simply consider 
> anything with a SELECT as needing a snapshot?


SELECT some_func();

Where some_func() does something that requires a snapshot.

> 
> Cheers,
> Greg
> 

-- 
Adrian Klaver
adrian.klaver@aklaver.com